Mis-feed detecting system



2, 1955 J. P. CONKLIN 3,264,630

' MIS-FEED DETECTING SYSTEM Original Filed June 5, 1961 5 Sheets-Sheet 1 W .III. I I 4 Q B INVENTVOR. \ToSPfl PeTmcK C'oNKLIN [1) 619mm l/Q. \Mfleuf ATTORNEY Original Filed June 5, 1961 Aug. 2, 1966 J. P. CONKLJN HIS-FEED DETECTING SYSTEM- SheetSQ-Sheet 2 7. 2 E .3 v WITH 154 {I 170 174 MLTU 54 1 1 7% Z l I 1 MAG 6Q 71 AND $3M AMF? f 3S AMP. CU, AHR AMP um'r 1 v k PHOTO on -ONE [P ONE gm AND st SHOT 5 sl m; ems J75 sno'r Pso/ P L 175 new AME I [new v j 84 17' ,4 1 W m sq. one MT s Cu SHOT AHP.

154 1 99 I PHOTOELECTRIC smsme own 5 pnowonzcwr s sme uNn' J fi\ v I 206' ma. TI"I\NG llllili -"1" 1 Hill 7 OR GATE 54 OR GATE on 17v 02. AND 182 15; GATE AMP. GATE ATE 2 AND AND a GATE GATE 154 170 J70 SEZ S'KA JTEF AMP GATE N 204 oesnq if; 54 g 476 J80 47; 182 5 ,QQ REM INVENTOR.

' CTosePH fimlckcanlxml '/170 AND 4 GATE A T TORNEY ON TIME g- .1 J. P. CONKLIN 3,264,630 MIS-FEED DETECT;[NG SYSTEM Original {filed Ju ne 5, 1961 a Sheets-Sheet a QVEZLAPPING LATE EARLY ON Tut-1E INV EN TOR.

JbseFH Pen/ck Com m1 BY wmmmwm ATTOQA/E 'Joseph Patri k Conklin, Falrlield,

This invention relates to an apparatus and method for detecting mis-feeds' among checks or. other documents being fediand, more particularly to an improvement over the mis-feed' detecting apparatus and .method disclosed in US. Patent No. 2,973,202 granted on February 28.

1961, to R. E. Schmeck et al. 1 Thisapplication is a continuation of.prior copending application Serial No. 114,696, filed June 5, 1961, and now abandoned.

When feeding a multiple number of checksor other documents simultaneously in end to end spaced relation in'cyclical sequence between a starting position and one or more operating positions, one or more of the documentsmay occasionally arrive at an operating position out of time, i.e., early or late. When the degree to which the document is out of time exceeds a particular tol- United States Patent erance, a jam may occur leading to thepossibility of damage-not only to the documents being fed but also to the feeding and/or other operating mechanism. As disclosedin the above-noted U.S. patent, jam prevention is accomplished by providing sensing means at a determined location along the document feed path; which sensing means causes an error signal to be produced whenevera space between two successive documents fails to be sensed at a determined time when this space is -.due atthat determined location. This error signal-hi dicates that a jam. may be imminent and is utilized to .stop the operatior. of the document feeding means thereby preventing the occurrence of a jam.

With the present invention, however. mis-fced'detectiou is accomplished by providing sensing means at a determined location along the'document feed path; which sensing means, causes a storage means to be set when a space between two successive documents fails to be sensed at a determined time during the feeding of each document. No error'signal is produced at this time,

feeding of the documents continues, and the sensing means continues to sense for a space between two successive documents. The storage means is arranged to be .reset, once it is set. whenever a space between docurnents being fed is sensed by the sensing means. If a f space between documents fails to be sensed by the sens ing means during a determined-time interval after setting of the storage means, an error signal is produced. This error signal indicates that a mis-teed has occurred and may be utilized to' stop the operation of the/document feeding means. If, however, the storage means is reset before said determined time interval terminates, no stop signal-is produced and feeding of the documents eontinucs without interruption. I

It will be apparent that with a mis-feeddetectihg apjparatus'that produces amis-feed indicating signal whenever a'space between successively fed documents of uniform length fails to be sensed at a time when such a space is due at the sensinglocation, the maximum to]- -erance (i.e., the maximum amount by which each document can lead or trail its on-time position without causing a mis feed indicating signal) is equal to the length (in the direction of feeding) of the space between each two successively fed on-time documents. In this regard. if any document being fed varies from its on-time position by an amount greater than the length of this space.

a spacebetweensuccessively fed documents will ncccs- I 3,264,630 Patented A g 1966 between the trail edge of the longest possible document and the lead edge of the next succeeding document). It sometimes, if not frequently, occurs, however, that the tolerance of the menus for operating on the documents being fed (such, for example, as sorting mechanism) is greater than the minimum (or uniform) length of the space-between the successively fed on-time documents. With the present invention, the maximum tolerance can readily be adjusted to an amount substantially greater as well as substantially smaller than the minimum length of space between the successively fed on-time' documents; all as will become apparent as thedescription proceeds.

Accordingly, an object of the present invention is to provide a new and improved apparatus and method for detecting document nus-feeds.

A further object of this invention is to provide such an apparatus and method which are readily capable of acan apparatus and method for dctccting mis-fecds such as jams, stream feeding, feeding of documentsthat are oversize in the direction of feeding, and documents being fed out-of'time.

Further objects and advantages will become as the description proceeds.

Several embodiments of the invention the accompanying drawing wherein:

FIG. 1 is a fragmentary. more orplan view of a document feeding and sorting machine which incorporates timing and sensing devices for misfced detection according to the present invention;

FIG. 2 is a block diagram of the electronic means of a mis-feed detecting system according to a first embodiment of the present invention;

FIG. 3 is a similar view of the electronic means of a this-feed detecting system according to a second embodiment of the present invention;

FIG. 4 is a fragmentary block diagram illustrating a modification applicable to the block diagrams of FIGS. 2 and 3;

FIG. 5 is a block diagram of the electronic means of a mis-fced detecting system for sensing fed documents at a pluralityof locations according to said Second embodiment of the invention: and I FIG. 6 isan electrical timing chart showing the pulse trains as they occur at respective locations within the block diagrams of FIGS. 2-4.

Referring to the drawing, FIG. shows a sorting apparatus including a separating apparent are shown in 1 diagrammatically and feed- .ing unit generally indicated at 10 for separating documents such as checks from a stack and for feeding the checks forwardly in one'by-one succession. More particularly, the separating and feeding unit 10 includes check advancing belts l2 continuously driven in the direction ofthe arrow in FIG. 1 about pulleys 14, '16 and 18. The unit 10 also includes separating belts 20 continuously driven in the direction of the arrow in FIG. 1 about pulleys 22, 24 and 26. For details, in addition to those set forth herein, of the check separating and [ceding unit and the remaining parts of the feeding and sorting machine shown in FIG. 1, reference may be had to the above-noted US. patent and to- US. Patent No. 2,977,114 granted on March 28, 196i, to W. J. Hanson ct al.

The checks are fed from the separating and feeding unit less diagrammatic i .3) in end to end spaced relation in cyclical sequence to a synchronizer generally indicated at 2.8. The synchronizer 28 includes a synclu'oni/cr disc 30 and idler rollers 32 be- .tween which the checks'are led in cyclical sequence.

After passing from between the synehronizer disc 30 and the uppermost one of the idler rollers 32 (as vieued in 'l'lCi. l), the ch ei tsare fed to the left (again as viewed in llU..l) in succession and along substantially a straight line bctwcen driven roller 34 and idler 36, between driven helts 38 and idler rollers 40, between driven belts 42 and idler rollers 44, and then to one of a plurality of successiv stacker stations designated by the reference numeral 46 (only one of the latter being shown in FIG. Each stacker station 46 includes driven belts 48, and

each successive check is fed between the belts 48 and idler I rollers 50 to a check deflecting element 52. When the defl'ectingelement 52 is in the position shown in FIG. 1,

tthe next successive check fed between belts 48 andidler irollers 50 will be deflected downwardly (as. viewed in QFIG. l) to a first stacker tnotshown). thcn however,

the deflecting element 52 is pivoted about an axis 54 to a clockwisejposition, the next successive check will continue to feed to. the left to the next stacker unit. It will be clear that the number of: stacker units 46 thatare pro-.

vided is determined by the particular installation' A motor indicated at 56 drives a shaft 60 which, in turn, drives a pulley 62 through a belt 64 and a pulley 66 fixed on the shaft-60. The stacker feed belts 48 are driven by -a pulley 68 fixed,- along with the pulley 62, on a shaft 70.

As can be seen in FIG. 1, stacker feed belts 48 are entrained about idler pulleys 721 74, 76 and 78 as well as about drivenpulley 68. A third pulley 80 fixed onthe shaft 70 drives a be'lt 82 which is also entrained about two pulley wheels 84 and 86. respectively. Pulley 84 is fixed on'a shaft 88 to drive two pulleys 90 and'92, respectively.

Pulley 90 drives a belt 94 and a pulley 96 fixed on a shaft 98t0 drive a pair of discs 100 which carry. two sets of l paddles 1 02.

100 in diametrically opposed relation to the other set, and

Each set of paddles is earried'by discs each set includes one paddle directly above another.

- Pulley 92 drives a belt 104 and a pulley 106, the latter beingrotatable about the shaft 98 with and fixed to the synchronizer disc'30. Through gearing shown at 108, the pulley 86 drives a shaft 110, and the latter drives separating belts 20 through a belt 112 and a pulley fixed on the shaft 116 to which pulley 2-1 is also fixed. The shaft 116 also drives a belt 118 to drive the pulley 16 fixed on the shaft 120. Another motor IZZ-drives a pulley 124, belt 126 andpulley 128. Pulley 128 is fixed to pulley 130 to I drive belts 42, the latter also being entrained about a pulley 132 and engaged by a take-up idler roller 134.

The checks are fed. as described above, in succession from the separating and feeding unit 10 to the synchronizer unit 28. and then .in substantially a straight line to the left (as viewed in FIG. 1) until deflected into one of the'stackers by a respective deflecting element 52. While being fed in said substantially straight line; the successive checks ordinarily travel at the cyclic rate of speed and with the lead edge of each check spaced a determined distan'ce ahead of thelettd edge of the next successive check. So long. as each check isnot oversize in the direction of feeding and is fed in timed relation, the successive checks will be fed in end to end spaced relation, that is, with 1 the trail edge of each check spaced ahead of the lead cdgeof the next succes ive check; The discs 100 of the syncht'oniicr unit 28.which carry the two sets of paddles 102 are driven at an angular speed proportional to the intended cyclic rate of feed of the checks. This speed is slightly slower than that at which the synchronizer disc 30 is driven. 'With proper feeding, each succes ive check is fed to the synchronixer unit 28 slightly late and is J urged by the synchronize! disc 30 in the direction of feeding ata slightly greater rate than that at which the two sets'of paddles 102 are moving with the result that the lead relative to the disc i edge of each check the sets of paddles sutnes the speed of lICl QUPUH the respective check asthe set of paddles and slips slightly 30. liach one of the two setsof paddles I02 l'CVCllVLw about the shaft S it once for each two cycles of the check feed. Accordingly, the successive checks are ordinarily ted very close to and ultimately in timed relation while traveling about the synchronizer disc 30, and then are fed in timed relation after leaving the synchronizcr disc 30 until deflected by one of the d efleeting elements 52. Occasionally; however, a mis-feed occurs and the present invention is directed to the detection of these nus-feeds,

In accomplishing misled detectiomthe present inventom-cs into engagement with one of tion can utilize document sensing units and magnetic timing units identical to those disclosed in the above-noted US. Patent No. 2,973,202. Referring toFIG. 1 in this regard, two magnetic timing units generally designated at 138 and 138n respcctively, are provided. These magnetic timing units are of conventional design and each includes a respective one of two magnetic devices 142 and 142a. Each of these magnetic devices includes a permanent magnet which produces a magnetic field within EMF. in the coil of the respective magnetic device" which is manifested as a change in the voltage across electrical leads to the ends of the coil; this voltage change being in the form of a sine wave.

(ill

One or. more photoelectric sensing units is associated with each of the magnetic timing units. In FIG. 1, each of the photoelectric sensing units generally designated at 146 is associated with the magnetic timing unit 138, and each ofthe photoelectric sensing units 1460 is associated with the magnetic timing unit 138a. Each of the photoelectric sensing units Mound 14611 includes a lamp 148 which projects a beam of light across the check feed path at a light-sensitive device such as a photo-transistor 150. The voltage output of each photo-transistor 150 varies between two levels depending upon whether or not one of the checks obstructs that photo-transistor from the light beam projected by the respeetive lamp 148 associated therewith.

For the purposes of description, the photoelectric sensing unit PSU in the electronic blockdiagram of the embodiment of FIG. 7. is representative of any one of the photoelectric sensing units 46 and 146a as shown in FIG. 1, and the magnetic timing unit MTU of FIG. 2 is representative of the respective one of magnetic timing units 138 and 138a of FIG. I associated therewith.

The output of the photoelectric sensing unit PSU is at one voltage level when therespective light beam is not interrupted by a check and is at a higher or more A positive level when a check does interrupt the respective light beam- Referring to FIG. 6, the pulse train 152 is one such as would be produced by the sensing unit PSU if an on-time check were fed past this sensing unit fol-- lowed in succession by an on-timc check, a late check,

an early check that overlaps or abuts the preceding late check, another late check and then a check which jams.

The trailing hall of each sine wave output of the magnetic timing unit MTU is shaped by a squaring circuit 154 (such as a Schmidt trigger) whose output is a train of negative going timing pulses as indicated at 156 in FIG. 6. Referring to HG. an amplifier 160 is associated witha dillerentiating network whereby the out put of the squaring circuit 154 is dill'erentiated and am plified to produce the spiltc pulse train 158. It will be clear I'rornthc wave-form chart of FIG. 6 that each timing pulse'of the train 156 is, in ctlcct, converted to a leadingpulse and a trailing pulse. in this regard, the lead of each of these timing pulses is converted to a positivegoing trail spike pulse. The'tra'il spike timing'pulses are spaced in time, each from the next,- to occur once during the same point in each succeeding check feed cycle. Each lead spike timing pulse occurs arm the next preceding trail spike timing pulse an amount of time just slightly less than-that until.the next'succeedinglead spike timing pulseoccurs;

" edge of each timingpulsc or the train 156 is converted toa negative-going lead spike pulse, and the trail edge vAn and gate 162 is connected as shown in FIG. 2

l to produce an output pulse (see pulse train 164) when any pulse fromthe photoelectric sensing unit PSU (pulse train 152) is being produced simultaneously with a, trail v; spike pulse from amplifier 160 (pulse-train 158). This occurs each time a check being fed is at the sensing location of the'sensing unit PSU when one of the trail spike timing pulses occurs. A flip-flop 166 of the smcalled unsymmetrically triggered type is provided whereby it is set bya pulse from a first source and is reset, by a pulse from a secondv source; The flip-flopv 166 iii-arranged as shown in 1 16.! such that it is set by any output pulse of the fand gate 162 and is reset. .once set, by the trail edge of the respective output pulse of the sensing unit check being fed is at the sensing location of the sensing unit PSU when one of the trail spike timing'pulses occurs, and once this flip-flop is set'itris resetwhenever a spacebetween checks is sensed at that sensing location.

The flip-flop 166 producesanegativegoingoutput pulse (see pulse train 168) while in; thevreset state. "An "and" gatel'lti is connected to produce an output (see PSU. Consequently, the flip-flop ltitiis set whenever a 172 in FIG. 6) whenever a lead spike pulseltom the V amplifier 160 occurs while the flip-flop 166 is' producing an output pulse. It follows that. once the flip-flop'166 is set. the "and gate 170 will produce an output-pulse if the next succeeding lead spike timing pulse occurs before the flip-flop is'set. Accordingly, if after setting I of the flip-flop, the. sensing unit senses a space between flip-flop 166tcmains in thc sci condition) from the time the leading edge oi thc third check is scnscd until the next succeeding lcad spikc tinting pulse (train 158) occurs, so I that the "and gait: 170 rcceivcs pulscs from thcamplifier The and" gate 160 and llip-llop 16o simultaneously. 170' responds by producinga nus-iced indicating pulse which is amplificd by the amplificr .174. The lead edge of thisamplitied pulsctriggcrs a onc-shot multivibrator '176 whose output drives a relay 178. The relay 178 may be utilized to stop the feeding of the checks as disclosed in the above-noted patent to R. E. Schmeck et al.

The fit'th check is not fed sufiicicntly latethat it overlaps (or abuts) the sixth check, whereby the flip-flop 166,, after beingset. is reset before the next succeeding lead spike. timing pulse occurs and no mis-fced indicatingpulse is produced by the -and" gate 170.

4 Assuming that the sixth check jams (stops being fed for any reason such as meeting with an obstruction), the I v f output pulse of the sensing unit PSU when this condition occurs, continues aftcrsctting of the flip-flop 166 until the next succeeding lead spike timing pulse occurs .with the result that the and gate 170 produces a mis-feed indicatingpulse.- With the embodiment of FIG. 2 as described above,

it will be apparent, then, that this arrangement was not sutiiciently sensitive that the fifth document which was fed late was'detected as a mis-feed, but this arrangement was sufficiently sensitive to detect the overlapping third and fourth documents and the jam of the sixth document as mis-feeds. Also, from the above description of the ernbodiment of FIG. 2. it will be apparent that the magnetic timing unit MTU, the squaring circuit 154 and the amplifier 160 operate as a timing. means for producing two timing-pulses during each check feed cycle. The photoclcctric sensing unit PSU operates to detect the presence and absence of a check at the sensing location of this sensing unit. 'Thc flip-fiop 166 acts as a storage means for storing the information that the sensing unit'PSU failed to sense a space between checks when the first one checks being fed beforethe next succeeding leadingspike timing pulse occurs. the and'jgate 170 will not'produce an outputfpulse; otherwism ihe and" gate 170 will proof the two timing pulses (the trailing positive-going spike pulse) occurred. The and" gate 170 operates as a misfeed indicating means which produces an output pulse when the flip-flop 166 fails to be reset, after being set,

before the second one of the two timing pulses (the sucd'uce an outputpulse, The output pulse by the and" gate l7 -tl is a mis-feed indicating signal.

. w The embodiment of FIG. 2 will now be described as it occurs when the feeding of checks is such that the pulse train 1510f FIG. 6 is produced by the sensing unit PSU, and whenthe magnetic timing unit MTU is arrangedtoproduce a lead, and trail spike timing pulse during a time interval when approximately the mid-- 7 point of each properly fed check is due at the sensing location of the sensing unit PSU. With the feeding of each of the first two (on-time) checks, the trail spike timing pulse of train 158 occurs while the sensing unit 4 rsu is; producingan outputpulseflraln tn) whereby the "and" gate l fiifpro duce's an output spike pulse (train 1 64.) which sets the flip-flop166. The resulting negative-' going output pulse of the flip-flop 166 (train 168) ter- ."minate's when thistlip-llop is reset-upon termination of the output pulse of the sensing unit PSU, as occurs when the trail edge'of each on-time check clears the sensing location-of the sensing unit PSU. Since theliip-llop 166 indicating pulse. and feeding of 'the two on-timechecks f continues uninterrupted. y V The third check is fed sufficiently late and the fourth check sufiiciently early that these two checks overlap each other; this; being known as astream feed) Consequently, the sensing unit PSU fails tosense a space between these two'checks'. More specificullyythefsensing unit PSU'continues to produce an output pulse (and the is reset before the next lead spikepulse of the train 158 occurs, the and" gate-170 produces no mis-fe ed of the sensing unit PSU terminates.

ceedingleading negativc-going spike pulse) occurs.

. The embodiment of F1653 differs substantially from I that of FIG. 2 only in the pro ision of a-dlfferent storage means. In this regard, thetiming unit MTU, squaring circuit 154, amplifier 160, sensing unit PSU, land" gate 170, amplifier-l74. one-shot multivibrator 176 and relay 178 of the embodiment of FIG. 3 operate in a manner identical to their respective counterparts in the embodi- -mcnt of FIG. '2.

In the embodiment of FIG. .3,

an or" gate 180 passes each trail spike timing pulse from the amplifier to the and gate 182.. v -Whcn the sensing unit PSU is producing an outputpulse (indicating that a space between checks is not then at the sensing location) at thetime that one of the trail spike timingpulses occurs, the and" gate 182 begins to produce an output pulse. The output of the and gate l82is amplified by an amplifier 184 and fed back to the and gate 182 through the or gate 180. Consequently, I once the and gate 182 begins to produce an output that the storage means of the embodiment of FIG. 3

operates in 'a manner similar to that of FIG. 2 in that setting of the storage means is effected when a trail-spike timing pulse occurs while the sensing unit is'producing w an output pulse, resetting of the storage means, once it and .156 in FIG:

adjusting the position of I the reset Iapped,.the sensing unit PSU was producing an out-put is-set, occurs'whcn the output pulse of the sensingunit PSU terminates, and the storage means produces an output pulse so long as it is in the set condition. Accordinglyfwith the magnetic timing unitMTU and photoelectric sensing unit PSU producing the pulse trains 152 i i 6 asdescribcd'above. the embodiment of FIG. 3 operates in a manner similar to and with the same sensitivity as the embodiment of.FIG. 2. With regard to the embodiment of FIG. 3, the output of the amplifier 160'Will be the same as the pulse train 158 of FIG. 6, the amplified output of the and gate v182 will be the same as the pulse train,168, and the output of the and? gate. 170 will be the same as. the pulse train 172.

The operation of the embodiment of FIG. 2 will now be described as it occurs under the same conditions as before (with the pulsetrain 152 of FIG. 6 being produced by the sensing unit PSU) except that the timing unit MTU is arranged such that a lead and trail timing pulse fromthe amplifier 160 occur when a space between checks being fed is due at the sensing location of the sensing unit PSU. (rather than: when the mid-point of each properly fed check is due at the sensing location as the pulse train 186-in FIG. 6, and the output of the amplifier 160 (in association with a differentiating network) will be the-pulse train 188. It is noted that the pulse trains 186 and 188are identical but shifted in-time relative to the pulse trains 156 and 158, respectively. As will become apparent, merely by so shifting the time at which the timing lpulses occur, the sensitivity of the mis-feed detecting-means is adjusted. I shifting of the timing pulses could be effected simply by buttons 144, 144 on-the discs 100.. Comparing the pulse .train 152 as produced by the sensingunit PSU with the pulse train 188, it is clear that no output pulse was being produced by the sensing unit PSU when the first two trail spike timing pulses of the "train 188 occurred; this being the case because .the

first two checks were properly fed on-time and each of the two trail spike timing pulses therefore occurred at a time when-a space between checks was at the sensing location. Consequently, no output was produced by the -"and gate 162 and the flip-flop 166 was not set. The output of the flip-flop 166 is depicted at 190 in FIG. 6. The third check, as indicated by the pulse train 152, was fed lateso that, again, no output pulse was being produced by-the sensing unit PSU when the third trail spike timing pulse occurred and the flip-flop 166 remained in state. Since the third and fourth checks over- It will be clear that this before). The output of the squaring circuit 154 will be pulse when the'fourth trail spike timing pulse occurred whereupon the flip-flop 166 was set and began producing pulse train 190). However, since' an output pulse (see the fourth check, even though it was early and overlapped the third check, cleared the sensing location ofthe sensing unit PSU before the next succeeding (fifth) lead spike timing pulse occurred, the flip-flop 166 was reset 'and. no mis-feed indicating pulse was produced by the and gate 170 as indicated by the pulse train 192 in FIG. 6. The fifth check was fed sufficiently late that the "sixth trail spike timing pulse occurred before the trail edge of this fifth check cleared the sensing location of the sensing unit PSU so that the flip-flop 166 was set. 'Shortly thereafter, the sensing unit PSU detected a space between the fifth and sixth checks whereupon the flip-flop 166 was reset before the next lead spike timing pulse occurred. When the sixth check jammed, the flip-flop 166 remained in the set state from the time the seventh trail spike tinting pulse occurred until the next succeeding lend spike timing pulse occurredso that the and gate 170 produced a mis-feed output pulse (see the negative-going pulse at the end of line 192 in FIG. 6).

It is clear, then, that merely by shifting in time the timing pulses as initiated by the timing unit MTU, the

sensitivity of the embodiment of FIG. 2. was decreased I sufficiently that the overlapping third and fourth checks were not detected as a mis-feed but the sensitivity was not decreased to the point that the jam failed to be detected. Such an arrangement would be advantageous in a situation where such overlapping documents merely result in I a mis-sort, and a mis-sort is preferred over stoppage of once each cyclic feed interval and the overlapping third and fourth documents prevent the sensing of such a space. for an interval substantially greater than one cyclic feed' interval.

Under the same conditions as just described with respect to the tion of the embodiment of FIG. 3 would be the same; the amplified output of the and" gate 182 being the same as that indicated at gate being the same as that indicated at 192.

FIG. 4 depicts a modification which can be applied to both of the embodiments of FIGS. 2 and 3 and by which the sensitivity of mis-feed detection can be adjusted in another way. 'As can be seen in FIG. 4, this modification involves-the provision of a one-shot multivibrator 194 between .the squaring circuit 154 and the amplifier 160. With this modification, the lead edge of eachtiming pulse as the one-shotmultivibrator 194 whereupon the latter produces an output pulse whose length can be chosen as desired. To demonstrate how the sensitivity can be adjusted, this modification will be described under the same conditions. as last described (whereby the sensing unit PSU produces the pulse train 152, and the output of the squaring circuit 154 is of the oneshot multivilu'ator is approximately one-half of the cyclic time interval (i.e., one-half of the interval. from the time the leading edge of one on-time check passes a given-point along the feed path until the leading edge of the next succeeding check if on-time passes the same point). With the output of the squaring circuit 154 as shown 31-186 in FIG. 6, the output of the one-shot multivibrator194 will be as depicted at 196 and the output 1 means is set each time an on-time check is fed, but the storage means is reset before the next succeeding leading (negative-gou spike timing pulse occurs. the overlapping third and fourth checks are fed, how

ever. the storage means fails to be reset before the next.

succeeding (fourth) leading spike timing pulse occurs whereby the respective and gate 170 produces a misfeed'indicating output pulse. When a check is merely fed late, as is the fifth check, the storage means againfails to be reset before the next succeeding leading spike timing pulse occurs so that the and gate again produces a mis-feed indicating output pulse. From the previous description. it will be obvious that the jamming of the sixth check to be fed also causes the respective and" gate 170 to produce a mis-feed indicating pulse. Ac- 'cordingly, merely by adjusting the length: of the timing output pulse of the squaring circuit 154, the sensitivity was'increased such that not only were the overlapping whenever a space between be sensed when due at the because such an apparatus requires that a space between checks be sensed,

embodiment of FIG. 2, the overall opera find '16 Output f the and:

shaped by the squaring circuit 154, triggers as depicted at 186 in FIG. 6) with the added factor that the length of each output pulse the output of the flip-flop 166 in feed interval. a associated with the timing unit 138 which is separate g from and out of synchronisin with the timing unit 138a third and fourth chucks detected as a mis-fced along with the jammed sixth check but so also was the fifth I check which was merely ted late.

The respective embodiments of the-invention will be as shown and described above with respect to FIGS. 2 and 3 when only a single photoelectric sensing unit is associated with a magnetic timing unit. Such an arrangement would be usctL'for example, whenjit could safely be assumed that once each of the successively fed checks moved past the sensing location of a single sensing unit without a mis-feed, it would continue to do so' until its respective destination was reached. Frequently, however,

l suchan assumption cannot safely be made. For this and apart one check feed interval, and the photoelectric sensing units 146a are spaced apart a multiple of the check feed interval from each other. Due to space limitations, however, neither of the sensing units 14.6 isspaced from anyone of the sensing units 146 a multiple of this check Consequently, the sensing unit's 1'46 are associated with the sensing units 146a. Referring to FIGS. 1 and 5, the two sensing units 146, 146 are associated with the magnetic timing unit 138, and the sensing units l46n are associatcd'with the magnetic timing unit I The output pulses of each of the sensing units 146, 146 pass through an or" gate2tl4 to one of the fiand gates l82. The'sensing units 1460 are divided into two groups generally designated at 206 and 208, re-

spectively: the output pulses of each-of the former group passing through an or gate 210 and the output pulses of each of the latter group passing through an or gate 212, to a respective one of the and gates 182. It is noted that a single squaring circuit 154 and a single amplifier 160 as well as a single timing unit MTU are utilizcd for the timing pulses which operate in conjunction with the sensing signals produced by the two groups 206 and 208 of sensing units; It will be clear that when any one of the three and" gates of FIG. 5 produces a misfecd detecting pulse .this pulse will pass through an or" gate 214, be amplified by the amplifier 174, and trigger the one-shot multivibrator 176 which drives the relay 178. r

Referring to FIG. 5,'it will be clear that a pulse will appear at the output of each one of the or gates 210 and 212 each time any one of the sensing units 146a connected thereto senses a check at its respective sensing location. This pulse will continue until all of the sensing units connected to the respective or" gate fail to sense a check. It could occur, therefore, that one of the checks being fed was sufliciently ahead ottime and another of the checks being fed was sufiicicntly behind time that the output pulse of the respective or gate continued long enough that a mis-feed indicating signal was produced even though neither of said two checks was individually out-of-time sulliciently tooverlap any other check or othc rwise to cause the production of a mis-feed indicating signal. Such a possibility is reduced, of course, by utilizing the two or" gates 210. and 212, and connecting one-half of the sensing units 1460 to each. Such a possibility could be eliminated altogether by connecting the output of each sensing unit 146a to a separate and" gate 182 which is otherwise connected in the same manner as each of the and gates 182 in .FIG. 5.

It will be clear from theabove description that in each case two timing signals occurred during each check feed cycle; the first one of these'two timing signals acted to set a storage means ifa check was then located along the 1 10 check feed path at the sensing location of the sensing means; once set the storage means was reset ii the sensing means sensed a space between checks being fed past the sensing location before the second one of the two timing signals occurred; and a mis-feed indicating signal was produced if the storage means failed to be reset before said secondoneof the two timing pulses occurred. Stated otherwise,a mis-feed indicating signal is produced each time the sensing means continuously senses the presence v of a document at the sensing location from the time the first one of the two timing signals occurs until the second one of the two timing signals occurs.

Since many changes can be made in the embodiments and the modification thereof as particularly described and shown herein without departing from the scope of the invention, it is intended that these embodiments and thev modification thereof be considered as exemplary and that the invention not be limited except as warranted by the following claims. 7 to those with only ordinary skill in the art that equivalent timing and document sensing means could be substituted for the magnetic timing units and photoelectric sensing units, respectively, as are described herein.

, What is;claimed is:

I. In an apparatus for successively feeding documents along a document feed path in end to end spacedrelation, and havingmeans operating in uniform timed cyclical sequence to feed one document during each cycle and establish a document feed cycle, a mis-feed detecting system comprising: a a

sensing means for sensing the presence and absence of a document at a predetermined location along said document feed path and providing corresponding presence and absence indicating signals; cyclical timing means opcratively connected to said feed ing means for producing serially a first timing signal and a second timing signal during each document feed cycle;

means opcratively connected to said sensing means and said cyclical timing means to produce a continuous signal actuated by the presence of both said presence signal from said sensing means and said first timing signal and said continuous signal continuing thereafter only during the continued presence of said presence signali and mis-feedindicating means operatively connected to said continuous signal means and said cyclical timing means to produce a mis-fecd indicating signal, re-' sponsive to the concurrence of said second timing signal and said continuous signal.

2. In an apparatus for successively feeding documents along a document feed path in end to end spaced relation, and having means operating in uniform. timed cyclical sequence to feed one document during each cycle and establish a document feed cycle, a nus-feed detecting system comprising:

sensing means for sensing the presence and absence of a document at a predetermined location along said document feed path and providing corresponding presence and absence indicating signals: cyclical timing means operatively connected to said feed- I ing means for producing serially a first timing signal 7 and a second timing signal during each document feed cycle; bistable storage means having set and reset positions operatively connected to said sensing means and said cyclical timing means to be set when a first timing signal occurs during a presence signal, and to be reset by said absence signal, said storage means providing a continuous signal in the set position; I and mis-fced indicating means operatively connected to said continuous signal means and said cyclical timing means to produce a mis-fced indicating signal, responsive to the concurrence of said second timing signal and said continuous signal.

By way of example, it will be. clear- 11 3. In an apparatus for successively feeding documents along a document feed path in end to end spaced relation, and having means operating in uniform timed cyclical sequence to iced one document during each cycle and establish a document feed cycle. a mis-feed detecting system comprising: 7

sensing means for sensing the presence and absence of a document at a predetermined location along said document feed path and providing corresponding presence and absence indicating signals; cyclical timing means operatively connected to said feeding means for producing serially a first timing pulse and a second timing pulse atpredetermined respective times during each document feed cycle; bistable settable storage means operable to produce a storage pulse only while in the set state; said storage means being operatively connected to said sensing means and to said cyclical timing means to be set whenever a presence signal is being produced at the time said first timing pulse occurs;

said storage means being further operatively connected to said sensing means to bev reset, once set, by said absence signal;

and an and" gate operatively connected to said storage means and'to said cyclical timing means for producing a mis-fe'ed indicating pulse, responsive to the concurrence'of said storage pulse and said timing pulse. 4. A mis-feed detecting system for use with an apparatus-including means for successively feeding documents along a document feed path in end to end spaced relationship and first timing means connected to a feeding means for initiating each successive document feed of said feeding means, and a document feed cycle defined by the time interval between successive initiation of said feeding means by said first timing means:

sensing means for sensing the presence or absence of a v documentat a predetermined location-along the document feed path and providing a corresponding pres- 3..1 ence indicating signal and abcnce indicating signal; second tinting means connected to said first timing means for producing a tit-st and second timing sig-""' nal. at predetermined times during catch said document feed cycle; bistable storage means having a set and reset condition,

corresponding set and reset inputs, and an output for providing a signal when in the set state;

an "and" gate having a first input connected to said sensing means and a second input connected to said second timing means and an output connected to said set input of said bistable storage means for placing said bistable storage means in the set state in response to the concurrent occurrence of a presence indicating signal and a first timing signal; means connecting said sensing means to said reset input of said bistable storage means for placing said stable storage means and an output connected to said.

mis-feed indicating means for energizing said misfeed indicating means in response to the concurrent occurrence of a set state signal from the output of said bistable storage means and said second timing signal to indieate'a mis-feed.

References Cited by the Examiner UNITED STATES PATENTS 3,046,538 7/1962 Pedersen 340-259 3,114,902 12/1963 Tanguy 340-259 3,136,423 6/1964 NEIL C.. READ, Primary Examiner. R. M. 'GOLDMAN, Assistant Examiner.

Dclplace 340-259 

1. IN AN APPARATUS FOR SUCCESSIVELY FEEDING DOCUMENTS ALONG A DOCUMENT FEED PATH IN END TO END SPACED RELATION, AND HAVING MEANS OPERATING IN UNIFORM TIMED CYCLICAL SEQUENCE TO FEED ONE DOCUMENT DURING EACH CYCLE AND ESTABLISH A DOCUMENT FEED CYCLE, A MIS-FEED DETECTING SYSTEM COMPRISING: SENSING MEANS FOR SENSING THE PRESENCE AND ABSENCE OF A DOCUMENT AT A PREDETERMINED LOCATION ALONG SAID DOCUMENT FEED PATH AND PROVIDING CORRESPONDING PRESENCE AND ABSENCE INDICATING SIGNALS; CYCLICAL TIMING MEANS OPERATIVELY CONNECTED TO SAID FEEDING MEANS FOR PRODUCING SERIALLY A FIRST TIMING SIGNAL AND A SECOND TIMING SIGNAL DURING EACH DOCUMENT FEED CYCLE; MEANS OPERATIVELY CONNECTED TO SAID SENSING MEANS AND SAID CYCLICAL TIMING MEANS TO PRODUCE A CONTINUOUS SIGNAL ACTUATED BY THE PRESENCE OF BOTH SAID PRESENCE SIGNAL FROM SAID SENSING MEANS AND SAID FIRST TIMING SIGNAL AND SAID CONTINUOUS SIGNAL CONTINUING THEREAFTER ONLY DURING THE CONTINUED PRESENCE OF SAID PRESENCE SIGNAL; AND MIS-FEED INDICATING MEANS OPERATIVELY CONNECTED TO SAID CONTINUOUS SIGNAL MEANS AND SAID CYCLICAL TIMING MEANS TO PRODUCE A MIS-FEED INDICATING SIGNAL, RESPONSIVE TO THE CONCURRENCE OF SAID SECOND TIMING SIGNAL AND SAID CONTINUOUS SIGNAL. 